Preparation of Drug-Eluting Microspheres Based on Semi-Interpenetrating Polymer Network of Modified Chitosan and Poly(2-acrylamide-2-methylpropanesulfonic acid)

Drug-eluting microspheres based on semi-interpenetrating polymer network (semi-IPN) of modified chitosan (Cs) and poly(2-acrylamide-2-methylpropanesulfonic acid) (PAMPS) were prepared. The preparation included two steps: polymerization of AMPS, formation of Cs/PAMPS microspheres and surface modification of the microspheres. The microspheres were characterized by FTIR analysis and microscope observation. The Cs/PAMPS microspheres showed regular spherical shape with different diameters ranging from 300 to 500 µm. Functional groups of –COOH, –SO3H were introduced into the microspheres, and doxorubicin (DOX) was successfully loaded into microspheres with an enhanced loading rate through ion-exchange interaction of –COOH, –SO3H with amino groups of DOX. Compared with chitosan microspheres, the modified Cs/PAMPS microspheres displayed obvious advantages such as improved drug loading rate, faster loading speed and sustained drug release profile. The drug-eluting microspheres were biocompatible, biodegradable, and could be potentially applied as arterial chemoembolization agent.